BLDC motors (brushless DC motors) have a particularly simple design. In contrast to conventional electric motors, BLDC motors do not have a mechanical commutator.
A magnetic rotary field for operating the BLDC motor can be produced using an inverter whose semiconductor circuit elements can be controlled in various ways for this purpose. The controlling can take place for example using pulse-width modulation (PWM), in block operation, using space vector modulation, triangle-square modulation, triangle-sine modulation, or flat-top modulation.
German Patent Application No. DE 10 2012 210 658 A1 describes that space vector modulation can be used to provide a magnetic rotary field through a circuit system fashioned as an inverter. For each phase, the inverter has a control stage having a high-side switch and a low-side switch. As a function of the angular position of the rotor, having a permanent magnet, of the BLDC motor, the high-side and low-side switches of the control stages are controlled in alternating fashion in order to set the magnetic rotary field.
The power with which the BLDC motor can be operated is a function of the power loss of the inverter. The power loss causes a heating of the inverter, which limits the maximum power of the BLDC motor.
Therefore, there is a need for increasing the power that can be supplied by such a circuit system.